\[13:05:11 CDT(-0500)\] <span style="color: black"> &lt;colinclark&gt; Looks to me like the general approach is based on a proposed W3C Microdata spec: <a href="http://www.w3.org/TR/html5/microdata.html" class="external-link" rel="nofollow">http://www.w3.org/TR/html5/microdata.html</a></span>